^○Dang An Binh¹, Bui Dieu Hang¹, Tran Vu Quynh Vy¹, Ngo Thuy Trang², Mai Trong Khoa², Trinh Thi Minh Chau³, Nguyen Xuan Canh⁴, Nguyen Thi Thu⁵ (1.Department of Nuclear Medicine, Cho Ray Hospital, Ho Chi Minh city, Viet Nam, 2.Nuclear Medicine and Oncology Center, Bach Mai Hospital, Ha Noi, Viet Nam, 3.Department of Nuclear Medicine, University Medical Center, Ho Chi Minh city, Viet Nam, 4.PET/CT & Cyclotron Unit, Cho Ray Hospital, Ho Chi Minh city, Viet Nam, 5.Nguyen Thi Thu, Center for Reseach and Production of Radioisotopes, Nuclear Research Institute, Da Lat, Viet Nam)